X0101 EFFECT 33 LIVE 2014-03-31 0001193125-14-096794 POS AM 0001525998 Rentech Nitrogen Partners, L.P. 333-187727 0001573520 Rentech Nitrogen Pasadena, LLC 333-187727-04 0001573518 Rentech Nitrogen Finance Corp 333-187727-03 0001573519 Rentech Nitrogen, LLC 333-187727-02 0001573521 Rentech Nitrogen Pasadena Holdings, LLC 333-187727-01